Surface covering material



Patented Aug. 12, 1941 SURFACE COVERING MATERIAL Walter WV. Durant, Old Greenwich, Conn., as-

,signor to American Cyanamid Company, New York, N. Y., a corporation of Maine No Drawing. Application November 30, 1939, Serial No. 306,902

3 Claims.

Thisinvention relates to the improvement in the alkali resistance of surface covering compositions such as floor covering compositions containing siccative binders.

An object of this invention is to improve the alkali resistance of surface covering compositions containing siccative binders.

This and other objects are attained by incorporating in a siccative composition which is to be used in a floor covering composition or other surface'covering composition a nitrile, containing at least one carbon-carbon double bond, preferably one containing a terminal carbon-carbon unsaturation.

The following example is given by Way of illustration and not in limitation.

Example 7 Parts by weight Binder 30 Wood flour 30 Whiting 2O Lithopone 2O Acrylonitrile 3 These substances with or without a small proportion of drier, e. g. 0.1% cobalt naphthenate, are mixed together, e. g. in an internal mixer. The compacted mass which is delivered from the mixer may be disintegrated, as by a set of scratch rolls which comprises a plurality of rolls having intermeshing teeth projecting from their surfaces. The resulting material is sheeted on calender rolls or optionally it may be further mixed and disintegrated and then calendered. The material may be calendered on to burlap or other fibrous backing if desired. The sheeted material is placed in a stoving oven through which a current of heated air from about 70 C. to about 90 C. is circulated until the material is completely seasoned, i. e. until the sheet acquires the necessary degree of hardness.

The hardness may be measured by any of the methods generally employed in the manufacture of linoleum. See the Federal Stock Catalogue (U. S. Government Printing Ofiice), section 4, part 5, pages LLL-L-35l et seq. and pages LLL-L- 361 et seq., for the method employed herein.

The time required for seasoning a 2 mm. sheet of the above composition is about twelve days. The resulting seasoned floor covering shows improved alkali resistance. One method of de termining alkali resistance is to measure the depth in millimeters to which a 5% solution of sodium hydroxide in water penetrates in one hour at a temperature of 70 F. By this method the alkali resistance of the seasoned sheets is about 0.17 mm. penetration.

The seasoning speed of a 2 mm. sheet of the same mixture which does not contain acrylonitrile is about twelve to fourteen days and the alkali resistance of such a composition is about 0.28 mm; The marked improvement obtained with my composition is outstanding inasmuch as I have found it to be very difficult to improve the alkali resistance by even as little as 0.01 mm.

The binders may be derived from the drying oils and may be made in any convenient Welllmown manner, such as the methods described in British Patent 305,656 or the binders may comprise any of the various alkyd resins having siccative properties. For drying oil binders, linseed oil is preferable for economic reasons but other siccative oils may be used such as, for example, menhaden or fish oil, tung oil, soy bean oil, perilla oil, oiticica oil, Scheiber oil, sunflower seed oil, etc. The term siccative oil as used herein is intended to include not only the socalled drying oils but also the so-called semidrying oils. Furthermore it is possible to use mixtures of siccative oils with other fatty oils of the non-drying type.

It may be preferable in the manufacture of linoleum to make use of so-called scrim-oil or shed oil either alone or fiuxed with rosin or other gums or resins and/or mixed with a proportion of the so-called mechanical oil. Either of these types of oils may be used singly if desired.

In the preparation of the siccative oil binders it is customary to use rosin in admixture with the oil although other substances of the same type may be used, e. g., kauri gum, Congo gum, ester gum, abietic acid and its esters, pimaric acid, etc.

Other siccative binders which may be used are the alkyd resins which have siccative properties. Among these, the drying oil modified reaction products of maleic or fumaric acid with terpenes and polyhydric alcohols are particularly desirable. Other alkyd resins which are modified with drying oils may be used such as the phthalic-glyceride resins, the glycol-maleic resins, and mixed resins such as the phthalicfumaric-glycol-glyceride resins.

Instead of wood flour and/or the whiting and lithopone used in the examples, other fillers or pigments may be used. Examples of such fillers are: cork, cellulose pulp, asbestos, cottonwood tree pulp, walnut shell meal, glass fibers, foliated glass, etc. Among the pigments which may be used the following are included: lithopone, barytes, Zinc oxide, titanium oxide, chromates, red lead, white lead, malachite green, chrome green, chrome yellow, Prussian blue, iron oxide, etc. Similarly dyes and lakes may be used if desirable.

It is generally preferable to use driers in the preparation of the binders. The drier is usually added to the binder during the oxidation process and if desirable additional drier may be added when the binder, fillers, etc., are mixed together. Suitable driers include the oil soluble salts such a the naphthenates, resinates and linoleates of cobalt, lead, manganese, zinc, and chromium. Only a small proportion of these driers based on the siccative oil content, is generally sufiicient, e. g. about 0.005-l%, although larger proportions may be used as expedient. Obviously various mixtures of driers may be used.

The term seasoning as applied to linoleum compositions indicates the process of curing by heating or equivalent treatment to polymerize and/or oxidize the composition to a stage wherein the floor covering is sufliciently hard and resistant to abrasion to be suitable for its intended purpose and yet is still sufficiently flexible to permit the usual bending and rolling required of linoleum. The term maturing is similarly used.

Other unsaturated nitriles may be used to improve the alkali resistanceof surface covering compositions, e. g. substituted acrylonitriles (such as methacrylonitrile and ethacrylonitrile), 4-butene-1-nitrile, the pentene-nitriles, etc

I have found that only a small proportion of the nitriles is generally sulficient, e. g. 0.1-5% of the siccative composition but obviously smaller or larger proportions may be used if desirable.

The nitrile may be added during the mixing of the binder with the fillers, etc., or it may be added before or during the oxidation of the binder.

Obviously many modifications in the processes and compositions described above may be made without departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. In a process of curing a surface covering composition including a siccative material selected from the group consisting of drying oils and drying oil modified polyhydric alcohol-polycarboxylic acid resins, the step which comprises adding to such a composition an unsaturated ni- 2. In a process of curing a surface covering composition including a siccative material selected from the group consisting of drying oils and drying oil modified polyhydric alcohol-polycarboxylic acid resins, the step which comprises adding to such a composition an unsaturated nitrile having a terminal carbon-carbon double bond.

3. In a process of curing a surface covering composition including a siccative material selected from the group consisting of drying oils and drying oil modified polyhydric alcohol-polycarboxylic acid resins, the step which comprises adding to such a composition acrylonitrile.

WALTER W. DURANT. 

